I talked to a manager at a local Apple store and after consulting with his techs he told me that they could do the update if I brought in my Mac Pro. Without paying for a full upgrade to PT 12 I thought my best bet would be to go to the one OS version both companies could agree on, Mavericks, only to find that option barred to me. On the other hand, DropBox has decided to drop support for Mac OS Mountain Lion or below. Now, Pro Tools 10 cannot run on anything past Mavericks with any certainty (actually, it's a disaster), although it worlks well with Mavericks. I also use DropBox to send music to clients and collaborators (mostly the latter these days. I use this machine for Pro Tools v.10.3.10. Here's my situation: I have a 2010 Mac Pro 5,5, running Mountain Lion (and Sierra on a separate drive). Sierra is limited to the following machines: MacBook (Late 2008 Aluminum, or Early 2009 or newer).The requirements for Mountain Lion and El Capitan are: Your only other upgrade is Mountain Lion (10.8) which is available in the USA (but not the UK) in the Apple Store:

Note that if your Mac is capable of handling Sierra this link is not available to you.

If it isn't, but is capable of handling El Capitan you can upgrade to that using this special link: If your Mac is capable of handling Sierra you can upgrade to that for free. I'm afraid Mavericks is no longer available.

Download mac os x 10.9 torrent